Ann Mk 1 was abused. At 15/16 she killed her father, was arrested, presumably went to juvenile detention/jail (?), got out, became a programmer on a time travel project, broke up with Martin, then decided to go back in time to kill her grandfather in order hopefully prevent own abuse from never happening. She killed her grandfather and go to jail for that murder in 1955. She hoped to fade out of existance when her grandfather was killed so she was at least partially suicidal. She was a criminal (ie committed numerous crimes in addtion to murder like robbery) and was not a very nice person.
Ann Mk 2 had a sad childhood because her father was a damaged drunk who died when she was 10. She became a programmer on a time travel project, got married to Martin, had an abortion, and started divorce proceedings. She blamed her father's abusive step-father for his premature death and decided go back in time try to convince her grandmother not to marry the abusive guy so that she could have a happy childhood. She was not a criminal except through inaction, but she must have been suicidal too because she apparently drunk herself to death in a snow drift in the past after deciding raising her father herself was a bad idea.
Mk 1 and Mk 2 create Mk 3's life. She happy enough that she's married to Martin and pregnant.
Reading helped my understanding of the story a lot, but I still couldn't track which Ann was speaking during the exitensial conversation they had on Nov 11, 1955. I don't know what the narrator could have done to make that clearer in audio.